| V-204425 | High | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using an empty password. | Configuring this setting for the SSH daemon provides additional assurance that remote logon via SSH will require a password, even in the event of misconfiguration elsewhere. |
| V-204424 | High | The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. | If an account has an empty password, anyone could log on and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments. |
| V-204502 | High | The Red Hat Enterprise Linux operating system must not have the telnet-server package installed. | It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often... |
| V-204627 | High | SNMP community strings on the Red Hat Enterprise Linux operating system must be changed from the default. | Whether active or not, default Simple Network Management Protocol (SNMP) community strings must be changed to maintain security. If the service is running with the default authenticators, anyone... |
| V-204621 | High | The Red Hat Enterprise Linux operating system must not have the Trivial File Transfer Protocol (TFTP) server package installed if not required for operational support. | If TFTP is required for operational support (such as the transmission of router configurations) its use must be documented with the Information System Security Officer (ISSO), restricted to only... |
| V-204620 | High | The Red Hat Enterprise Linux operating system must not have a File Transfer Protocol (FTP) server package installed unless needed. | The FTP service provides an unencrypted remote access that does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to log on using... |
| V-214799 | High | The Red Hat Enterprise Linux operating system must be configured so that the cryptographic hash of system files and commands matches vendor values. | Without cryptographic integrity protections, system command and files can be altered by unauthorized users without detection.
Cryptographic mechanisms used for protecting the integrity of... |
| V-204594 | High | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon is configured to only use the SSHv2 protocol. | SSHv1 is an insecure implementation of the SSH protocol and has many well-known vulnerability exploits. Exploits of the SSH daemon could provide immediate root access to the system.
Satisfies:... |
| V-204392 | High | The Red Hat Enterprise Linux operating system must be configured so that the file permissions, ownership, and group membership of system files and commands match the vendor values. | Discretionary access control is weakened if a user or group has access permissions to system files and directories greater than the default.
Satisfies: SRG-OS-000257-GPOS-00098, SRG-OS-000278-GPOS-00108 |
| V-204497 | High | The Red Hat Enterprise Linux operating system must implement NIST FIPS-validated cryptography for the following: to provision digital signatures, to generate cryptographic hashes, and to protect data requiring data-at-rest protections in accordance with applicable federal laws, Executive Orders, directives, policies, regulations, and standards. | Use of weak or untested encryption algorithms undermines the purposes of using encryption to protect data. The operating system must implement cryptographic modules adhering to the higher... |
| V-251702 | High | The Red Hat Enterprise Linux operating system must not have accounts configured with blank or null passwords. | If an account has an empty password, anyone could log on and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments. |
| V-204462 | High | The Red Hat Enterprise Linux operating system must be configured so that the root account must be the only account having unrestricted access to the system. | If an account other than root also has a User Identifier (UID) of "0", it has root authority, giving that account unrestricted access to the entire operating system. Multiple accounts with a UID... |
| V-204458 | High | The Red Hat Enterprise Linux operating system must be a vendor supported release. | An operating system release is considered "supported" if the vendor continues to provide security patches for the product. With an unsupported release, it will not be possible to resolve security... |
| V-204456 | High | The Red Hat Enterprise Linux operating system must be configured so that the x86 Ctrl-Alt-Delete key sequence is disabled in the Graphical User Interface. | A locally logged-on user who presses Ctrl-Alt-Delete, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of a mixed OS environment, this can create... |
| V-204455 | High | The Red Hat Enterprise Linux operating system must be configured so that the x86 Ctrl-Alt-Delete key sequence is disabled on the command line. | A locally logged-on user who presses Ctrl-Alt-Delete, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of a mixed OS environment, this can create... |
| V-204440 | High | Red Hat Enterprise Linux operating systems version 7.2 or newer using Unified Extensible Firmware Interface (UEFI) must require authentication upon booting into single-user and maintenance modes. | If the system does not require valid authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to all... |
| V-204443 | High | The Red Hat Enterprise Linux operating system must not have the ypserv package installed. | Removing the "ypserv" package decreases the risk of the accidental (or intentional) activation of NIS or NIS+ services. |
| V-204442 | High | The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. | It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often... |
| V-204447 | High | The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. | Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has... |
| V-204448 | High | The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. | Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has... |
| V-214801 | High | The Red Hat Enterprise Linux operating system must use a virus scan program. | Virus scanning software can be used to protect a system from penetration from computer viruses and to limit their spread through intermediate systems.
The virus scanning software should be... |
| V-204432 | High | The Red Hat Enterprise Linux operating system must not allow an unattended or automatic logon to the system via a graphical user interface. | Failure to restrict system access to authenticated users negatively impacts operating system security. |
| V-204433 | High | The Red Hat Enterprise Linux operating system must not allow an unrestricted logon to the system. | Failure to restrict system access to authenticated users negatively impacts operating system security. |
| V-204438 | High | Red Hat Enterprise Linux operating systems version 7.2 or newer with a Basic Input/Output System (BIOS) must require authentication upon booting into single-user and maintenance modes. | If the system does not require valid authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to all... |
| V-204607 | High | The Red Hat Enterprise Linux operating system must not contain shosts.equiv files. | The shosts.equiv files are used to configure host-based authentication for the system via SSH. Host-based authentication is not sufficient for preventing unauthorized access to the system, as it... |
| V-204606 | High | The Red Hat Enterprise Linux operating system must not contain .shosts files. | The .shosts files are used to configure host-based authentication for individual users or the system via SSH. Host-based authentication is not sufficient for preventing unauthorized access to the... |
| V-204427 | Medium | The Red Hat Enterprise Linux operating system must be configured to lock accounts for a minimum of 15 minutes after three unsuccessful logon attempts within a 15-minute timeframe. | By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the... |
| V-204426 | Medium | The Red Hat Enterprise Linux operating system must disable account identifiers (individuals, groups, roles, and devices) if the password expires. | Inactive identifiers pose a risk to systems and applications because attackers may exploit an inactive identifier and potentially obtain undetected access to the system. Owners of inactive... |
| V-204423 | Medium | The Red Hat Enterprise Linux operating system must be configured so that passwords are a minimum of 15 characters in length. | The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.
Password complexity, or strength, is a measure of the... |
| V-204422 | Medium | The Red Hat Enterprise Linux operating system must be configured so that passwords are prohibited from reuse for a minimum of five generations. | Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. If the information system or application allows the... |
| V-204421 | Medium | The Red Hat Enterprise Linux operating system must be configured so that existing passwords are restricted to a 60-day maximum lifetime. | Any password, no matter how complex, can eventually be cracked. Therefore, passwords need to be changed periodically. If the operating system does not limit the lifetime of passwords and force... |
| V-204420 | Medium | The Red Hat Enterprise Linux operating system must be configured so that passwords for new users are restricted to a 60-day maximum lifetime. | Any password, no matter how complex, can eventually be cracked. Therefore, passwords need to be changed periodically. If the operating system does not limit the lifetime of passwords and force... |
| V-204540 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all unsuccessful account access events. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204541 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all successful account access events. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204542 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the passwd command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204543 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the unix_chkpwd command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204544 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the gpasswd command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204469 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local interactive user home directories are owned by their respective users. | If a local interactive user does not own their home directory, unauthorized users could access or modify the user's files, and the users may not be able to access their own files. |
| V-204429 | Medium | The Red Hat Enterprise Linux operating system must be configured so that users must provide a password for privilege escalation. | Without re-authentication, users may access resources or perform tasks for which they do not have authorization.
When operating systems provide the capability to escalate a functional... |
| V-204428 | Medium | The Red Hat Enterprise Linux operating system must lock the associated account after three unsuccessful root logon attempts are made within a 15-minute period. | By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute forcing, is reduced. Limits are imposed by locking the... |
| V-204468 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local interactive user home directories have mode 0750 or less permissive. | Excessive permissions on local interactive user home directories may allow unauthorized access to user files by other users. |
| V-204591 | Medium | The Red Hat Enterprise Linux operating system must display the date and time of the last successful account logon upon an SSH logon. | Providing users with feedback on when account accesses via SSH last occurred facilitates user recognition and reporting of unauthorized account use. |
| V-204590 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using rhosts authentication. | Configuring this setting for the SSH daemon provides additional assurance that remote logon via SSH will require a password, even in the event of misconfiguration elsewhere. |
| V-204632 | Medium | The Red Hat Enterprise Linux operating system must implement multifactor authentication for access to privileged accounts via pluggable authentication modules (PAM). | Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect... |
| V-204633 | Medium | The Red Hat Enterprise Linux operating system must implement certificate status checking for PKI authentication. | Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect... |
| V-204630 | Medium | The Red Hat Enterprise Linux operating system must not forward IPv6 source-routed packets. | Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security... |
| V-204631 | Medium | The Red Hat Enterprise Linux operating system must have the required packages for multifactor authentication installed. | Using an authentication device, such as a CAC or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect... |
| V-204634 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all wireless network adapters are disabled. | The use of wireless networking can introduce many different attack vectors into the organization's network. Common attack vectors such as malicious association and ad hoc networks will allow an... |
| V-204503 | Medium | The Red Hat Enterprise Linux operating system must be configured so that auditing is configured to produce records containing information to establish what type of events occurred, where the events occurred, the source of the events, and the outcome of the events. These audit records must also identify individual identities of group account users. | Without establishing what type of events occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack.
Audit record content that may be... |
| V-204604 | Medium | The Red Hat Enterprise Linux operating system must enable an application firewall, if available. | Firewalls protect computers from network attacks by blocking or limiting access to open network ports. Application firewalls limit which applications are allowed to communicate over the... |
| V-204539 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the setfiles command. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204538 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the chcon command. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204537 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the setsebool command. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204536 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the semanage command. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204531 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the creat, open, openat, open_by_handle_at, truncate, and ftruncate syscalls. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204559 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the create_module syscall. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204558 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the pam_timestamp_check command. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204553 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the umount command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204467 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local interactive users have a home directory assigned and defined in the /etc/passwd file. | If local interactive users are not assigned a valid home directory, there is no place for the storage and control of files they should own.
In addition, if a local interactive user has a home... |
| V-204551 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the chsh command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204550 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the newgrp command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204557 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the crontab command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204556 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the ssh-keysign command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204555 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the postqueue command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204466 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local interactive user accounts, upon creation, are assigned a home directory. | If local interactive users are not assigned a valid home directory, there is no place for the storage and control of files they should own. |
| V-204546 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the userhelper command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204510 | Medium | The Red Hat Enterprise Linux operating system must encrypt the transfer of audit records off-loaded onto a different system or media from the system being audited. | Information stored in one location is vulnerable to accidental or incidental deletion or alteration.
Off-loading is a common process in information systems with limited audit storage... |
| V-204547 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the su command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-255925 | Medium | The Red Hat Enterprise Linux operating system SSH server must be configured to use only FIPS-validated key exchange algorithms. | The use of FIPS-validated cryptographic algorithms is enforced by enabling kernel FIPS mode. In the event that kernel FIPS mode is disabled, the use of nonvalidated cryptographic algorithms will... |
| V-204625 | Medium | The Red Hat Enterprise Linux operating system must not be performing packet forwarding unless the system is a router. | Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this software is used when not required, system network information may be... |
| V-204624 | Medium | The Red Hat Enterprise Linux operating system must not have a graphical display manager installed unless approved. | Internet services that are not required for system or application processes must not be active to decrease the attack surface of the system. Graphical display managers have a long history of... |
| V-204626 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the Network File System (NFS) is configured to use RPCSEC_GSS. | When an NFS server is configured to use RPCSEC_SYS, a selected userid and groupid are used to handle requests from the remote user. The userid and groupid could mistakenly or maliciously be set... |
| V-204623 | Medium | The Red Hat Enterprise Linux operating system must be configured so that if the Trivial File Transfer Protocol (TFTP) server is required, the TFTP daemon is configured to operate in secure mode. | Restricting TFTP to a specific directory prevents remote users from copying, transferring, or overwriting system files. |
| V-204622 | Medium | The Red Hat Enterprise Linux operating system must be configured so that remote X connections are disabled except to fulfill documented and validated mission requirements. | The security risk of using X11 forwarding is that the client's X11 display server may be exposed to attack when the SSH client requests forwarding. A system administrator may have a stance in... |
| V-255928 | Medium | The Red Hat Enterprise Linux operating system must be configured to prevent overwriting of custom authentication configuration settings by the authconfig utility. | When using the authconfig utility to modify authentication configuration settings, the "system-auth" and "password-auth" files and any custom settings that they may contain are overwritten. This... |
| V-204416 | Medium | The Red Hat Enterprise Linux operating system must be configured to use the shadow file to store only encrypted representations of passwords. | Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily... |
| V-204629 | Medium | The Red Hat Enterprise Linux operating system must not have unauthorized IP tunnels configured. | IP tunneling mechanisms can be used to bypass network filtering. If tunneling is required, it must be documented with the Information System Security Officer (ISSO). |
| V-204628 | Medium | The Red Hat Enterprise Linux operating system access control program must be configured to grant or deny system access to specific hosts and services. | If the systems access control program is not configured with appropriate rules for allowing and denying access to system network resources, services may be accessible to unauthorized hosts. |
| V-204417 | Medium | The Red Hat Enterprise Linux operating system must be configured so that user and group account administration utilities are configured to store only encrypted representations of passwords. | Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily... |
| V-256970 | Medium | The Red Hat Enterprise Linux operating system must be configured to allow sending email notifications of configuration changes and adverse events to designated personnel. | Unauthorized changes to the baseline configuration could make the system vulnerable to various attacks or allow unauthorized access to the operating system. Changes to operating system... |
| V-204616 | Medium | The Red Hat Enterprise Linux operating system must not allow interfaces to perform Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirects by default. | ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table, possibly... |
| V-204434 | Medium | The Red Hat Enterprise Linux operating system must not allow users to override SSH environment variables. | Failure to restrict system access to authenticated users negatively impacts operating system security. |
| V-204399 | Medium | The Red Hat Enterprise Linux operating system must prevent a user from overriding the screensaver lock-delay setting for the graphical user interface. | A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the... |
| V-204398 | Medium | The Red Hat Enterprise Linux operating system must initiate a screensaver after a 15-minute period of inactivity for graphical user interfaces. | A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the... |
| V-204568 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/security/opasswd. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-214937 | Medium | The Red Hat Enterprise Linux operating system must prevent a user from overriding the screensaver lock-enabled setting for the graphical user interface. | A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to log out because of the... |
| V-204395 | Medium | The Red Hat Enterprise Linux operating system must display the Standard Mandatory DoD Notice and Consent Banner before granting local or remote access to the system via a command line user logon. | Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal... |
| V-204394 | Medium | The Red Hat Enterprise Linux operating system must display the approved Standard Mandatory DoD Notice and Consent Banner before granting local or remote access to the system via a graphical user logon. | Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal... |
| V-204397 | Medium | The Red Hat Enterprise Linux operating system must uniquely identify and must authenticate users using multifactor authentication via a graphical user logon. | To assure accountability and prevent unauthenticated access, users must be identified and authenticated to prevent potential misuse and compromise of the system.
Multifactor solutions that... |
| V-204396 | Medium | The Red Hat Enterprise Linux operating system must enable a user session lock until that user re-establishes access using established identification and authentication procedures. | A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to log out because of the... |
| V-204562 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the delete_module syscall. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204393 | Medium | The Red Hat Enterprise Linux operating system must display the Standard Mandatory DoD Notice and Consent Banner before granting local or remote access to the system via a graphical user logon. | Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal... |
| V-204572 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the unlink, unlinkat, rename, renameat, and rmdir syscalls. | If the system is not configured to audit certain activities and write them to an audit log, it is more difficult to detect and track system compromises and damages incurred during a system... |
| V-204575 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the rsyslog daemon does not accept log messages from other servers unless the server is being used for log aggregation. | Unintentionally running a rsyslog server accepting remote messages puts the system at increased risk. Malicious rsyslog messages sent to the server could exploit vulnerabilities in the server... |
| V-204492 | Medium | The Red Hat Enterprise Linux operating system must disable Kernel core dumps unless needed. | Kernel core dumps may contain the full contents of system memory at the time of the crash. Kernel core dumps may consume a considerable amount of disk space and may result in denial of service by... |
| V-204490 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the cron.allow file, if it exists, is owned by root. | If the owner of the "cron.allow" file is not set to root, the possibility exists for an unauthorized user to view or to edit sensitive information. |
| V-204491 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the cron.allow file, if it exists, is group-owned by root. | If the group owner of the "cron.allow" file is not set to root, sensitive information could be viewed or edited by unauthorized users. |
| V-244557 | Medium | Red Hat Enterprise Linux operating systems version 7.2 or newer booted with a BIOS must have a unique name for the grub superusers account when booting into single-user and maintenance modes. | If the system does not require valid authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to all... |
| V-204470 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local interactive user home directories are group-owned by the home directory owners primary group. | If the Group Identifier (GID) of a local interactive user's home directory is not the same as the primary GID of the user, this would allow unauthorized access to the user's files, and users that... |
| V-204418 | Medium | The Red Hat Enterprise Linux operating system must be configured so that passwords for new users are restricted to a 24 hours/1 day minimum lifetime. | Enforcing a minimum password lifetime helps to prevent repeated password changes to defeat the password reuse or history enforcement requirement. If users are allowed to immediately and... |
| V-204419 | Medium | The Red Hat Enterprise Linux operating system must be configured so that passwords are restricted to a 24 hours/1 day minimum lifetime. | Enforcing a minimum password lifetime helps to prevent repeated password changes to defeat the password reuse or history enforcement requirement. If users are allowed to immediately and... |
| V-204471 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all files and directories contained in local interactive user home directories have a valid owner. | Unowned files and directories may be unintentionally inherited if a user is assigned the same User Identifier "UID" as the UID of the un-owned files. |
| V-204412 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed a minimum of four character classes must be changed. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204413 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed the number of repeating consecutive characters must not be more than three characters. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204410 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed or new passwords are established, the new password must contain at least one special character. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204411 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed a minimum of eight of the total number of characters must be changed. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-256969 | Medium | The Red Hat Enterprise Linux operating system must disable the login screen user list for graphical user interfaces. | Leaving the user list enabled is a security risk as it allows anyone with physical access to the system to enumerate known user accounts without authenticated access to the system. |
| V-256968 | Medium | The Red Hat Enterprise Linux operating system must ensure cryptographic verification of vendor software packages. | Cryptographic verification of vendor software packages ensures that all software packages are obtained from a valid source and protects against spoofing that could lead to installation of malware... |
| V-204414 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed the number of repeating characters of the same character class must not be more than four characters. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204415 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the PAM system service is configured to store only encrypted representations of passwords. | Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily... |
| V-204478 | Medium | The Red Hat Enterprise Linux operating system must be configured so that local initialization files do not execute world-writable programs. | If user start-up files execute world-writable programs, especially in unprotected directories, they could be maliciously modified to destroy user files or otherwise compromise the system at the... |
| V-204479 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all system device files are correctly labeled to prevent unauthorized modification. | If an unauthorized or modified device is allowed to exist on the system, there is the possibility the system may perform unintended or unauthorized operations. |
| V-228563 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all world-writable directories are owned by root, sys, bin, or an application user. | If a world-writable directory is not owned by root, sys, bin, or an application User Identifier (UID), unauthorized users may be able to modify files created by others.
The only authorized public... |
| V-228564 | Medium | The Red Hat Enterprise Linux operating system must protect audit information from unauthorized read, modification, or deletion. | If audit information were to become compromised, then forensic analysis and discovery of the true source of potentially malicious system activity is impossible to achieve.
To ensure the veracity... |
| V-204574 | Medium | The Red Hat Enterprise Linux operating system must send rsyslog output to a log aggregation server. | Sending rsyslog output to another system ensures that the logs cannot be removed or modified in the event that the system is compromised or has a hardware failure. |
| V-204577 | Medium | The Red Hat Enterprise Linux operating system must be configured to prohibit or restrict the use of functions, ports, protocols, and/or services, as defined in the Ports, Protocols, and Services Management Component Local Service Assessment (PPSM CLSA) and vulnerability assessments. | In order to prevent unauthorized connection of devices, unauthorized transfer of information, or unauthorized tunneling (i.e., embedding of data types within data types), organizations must... |
| V-204579 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all network connections associated with a communication session are terminated at the end of the session or after 15 minutes of inactivity from the user at a command prompt, except to fulfill documented and validated mission requirements. | Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port... |
| V-204578 | Medium | The Red Hat Enterprise Linux 7 operating system must implement DoD-approved encryption to protect the confidentiality of SSH connections. | Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and DoD data may be... |
| V-204472 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all files and directories contained in local interactive user home directories are group-owned by a group of which the home directory owner is a member. | If a local interactive user's files are group-owned by a group of which the user is not a member, unintended users may be able to access them. |
| V-204473 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all files and directories contained in local interactive user home directories have a mode of 0750 or less permissive. | If a local interactive user files have excessive permissions, unintended users may be able to access or modify them. |
| V-204474 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local initialization files for interactive users are owned by the home directory user or root. | Local initialization files are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon. |
| V-204475 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local initialization files for local interactive users are be group-owned by the users primary group or root. | Local initialization files for interactive users are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon. |
| V-204476 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local initialization files have mode 0740 or less permissive. | Local initialization files are used to configure the user's shell environment upon logon. Malicious modification of these files could compromise accounts upon logon. |
| V-204477 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all local interactive user initialization files executable search paths contain only paths that resolve to the users home directory. | The executable search path (typically the PATH environment variable) contains a list of directories for the shell to search to find executables. If this path includes the current working directory... |
| V-254523 | Medium | The Red Hat Enterprise Linux operating system must automatically expire temporary accounts within 72 hours. | Temporary accounts are privileged or nonprivileged accounts that are established during pressing circumstances, such as new software or hardware configuration or an incident response, where the... |
| V-204487 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all world-writable directories are group-owned by root, sys, bin, or an application group. | If a world-writable directory is not group-owned by root, sys, bin, or an application Group Identifier (GID), unauthorized users may be able to modify files created by others.
The only authorized... |
| V-204481 | Medium | The Red Hat Enterprise Linux operating system must prevent files with the setuid and setgid bit set from being executed on file systems that are used with removable media. | The "nosuid" mount option causes the system to not execute "setuid" and "setgid" files with owner privileges. This option must be used for mounting any file system not containing approved "setuid"... |
| V-204480 | Medium | The Red Hat Enterprise Linux operating system must be configured so that file systems containing user home directories are mounted to prevent files with the setuid and setgid bit set from being executed. | The "nosuid" mount option causes the system to not execute setuid and setgid files with owner privileges. This option must be used for mounting any file system not containing approved setuid and... |
| V-204483 | Medium | The Red Hat Enterprise Linux operating system must prevent binary files from being executed on file systems that are being imported via Network File System (NFS). | The "noexec" mount option causes the system to not execute binary files. This option must be used for mounting any file system not containing approved binary files as they may be incompatible.... |
| V-204482 | Medium | The Red Hat Enterprise Linux operating system must prevent files with the setuid and setgid bit set from being executed on file systems that are being imported via Network File System (NFS). | The "nosuid" mount option causes the system to not execute "setuid" and "setgid" files with owner privileges. This option must be used for mounting any file system not containing approved "setuid"... |
| V-204554 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the postdrop command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204593 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using known hosts authentication. | Configuring this setting for the SSH daemon provides additional assurance that remote logon via SSH will require a password, even in the event of misconfiguration elsewhere. |
| V-204489 | Medium | The Red Hat Enterprise Linux operating system must have cron logging implemented. | Cron logging can be used to trace the successful or unsuccessful execution of cron jobs. It can also be used to spot intrusions into the use of the cron facility by unauthorized and malicious users. |
| V-204488 | Medium | The Red Hat Enterprise Linux operating system must set the umask value to 077 for all local interactive user accounts. | The umask controls the default access mode assigned to newly created files. A umask of 077 limits new files to mode 700 or less permissive. Although umask can be represented as a four-digit... |
| V-204409 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed or new passwords are assigned, the new password must contain at least one numeric character. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204408 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed or new passwords are established, the new password must contain at least one lower-case character. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204405 | Medium | The Red Hat Enterprise Linux operating system must be configured so that /etc/pam.d/passwd implements /etc/pam.d/system-auth when changing passwords. | Pluggable authentication modules (PAM) allow for a modular approach to integrating authentication methods. PAM operates in a top-down processing model and if the modules are not listed in the... |
| V-204404 | Medium | The Red Hat Enterprise Linux operating system must initiate a session lock for graphical user interfaces when the screensaver is activated. | A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the... |
| V-204407 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed or new passwords are established, the new password must contain at least one upper-case character. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204406 | Medium | The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed or new passwords are established, pwquality must be used. | Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in... |
| V-204400 | Medium | The Red Hat Enterprise Linux operating system must prevent a user from overriding the session idle-delay setting for the graphical user interface. | A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the... |
| V-204403 | Medium | The Red Hat Enterprise Linux operating system must prevent a user from overriding the screensaver idle-activation-enabled setting for the graphical user interface. | A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to log out because of the... |
| V-204402 | Medium | The Red Hat Enterprise Linux operating system must initiate a session lock for the screensaver after a period of inactivity for graphical user interfaces. | A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the... |
| V-204504 | Medium | The Red Hat Enterprise Linux operating system must shut down upon audit processing failure, unless availability is an overriding concern. If availability is a concern, the system must alert the designated staff (System Administrator [SA] and Information System Security Officer [ISSO] at a minimum) in the event of an audit processing failure. | It is critical for the appropriate personnel to be aware if a system is at risk of failing to process audit logs as required. Without this notification, the security personnel may be unaware of an... |
| V-251705 | Medium | The Red Hat Enterprise Linux operating system must use a file integrity tool to verify correct operation of all security functions. | Without verification of the security functions, security functions may not operate correctly, and the failure may go unnoticed. Security function is defined as the hardware, software, and/or... |
| V-204506 | Medium | The Red Hat Enterprise Linux operating system must be configured to off-load audit logs onto a different system or storage media from the system being audited. | Information stored in one location is vulnerable to accidental or incidental deletion or alteration.
Off-loading is a common process in information systems with limited audit storage... |
| V-204507 | Medium | The Red Hat Enterprise Linux operating system must take appropriate action when the remote logging buffer is full. | Information stored in one location is vulnerable to accidental or incidental deletion or alteration.
Off-loading is a common process in information systems with limited audit storage... |
| V-204500 | Medium | The Red Hat Enterprise Linux operating system must use a file integrity tool that is configured to use FIPS 140-2 approved cryptographic hashes for validating file contents and directories. | File integrity tools use cryptographic hashes for verifying file contents and directories have not been altered. These hashes must be FIPS 140-2 approved cryptographic hashes.
Red Hat Enterprise... |
| V-204501 | Medium | The Red Hat Enterprise Linux operating system must not allow removable media to be used as the boot loader unless approved. | Malicious users with removable boot media can gain access to a system configured to use removable media as the boot loader. If removable media is designed to be used as the boot loader, the... |
| V-251703 | Medium | The Red Hat Enterprise Linux operating system must specify the default "include" directory for the /etc/sudoers file. | The "sudo" command allows authorized users to run programs (including shells) as other users, system users, and root. The "/etc/sudoers" file is used to configure authorized "sudo" users as well... |
| V-204463 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all files and directories have a valid owner. | Unowned files and directories may be unintentionally inherited if a user is assigned the same User Identifier "UID" as the UID of the un-owned files. |
| V-250312 | Medium | The Red Hat Enterprise Linux operating system must confine SELinux users to roles that conform to least privilege. | Preventing nonprivileged users from executing privileged functions mitigates the risk that unauthorized individuals or processes may gain unnecessary access to information or... |
| V-204460 | Medium | The Red Hat Enterprise Linux operating system must not have unnecessary accounts. | Accounts providing no operational purpose provide additional opportunities for system compromise. Unnecessary accounts include user accounts for individuals not requiring access to the system and... |
| V-204508 | Medium | The Red Hat Enterprise Linux operating system must label all off-loaded audit logs before sending them to the central log server. | Information stored in one location is vulnerable to accidental or incidental deletion or alteration.
Off-loading is a common process in information systems with limited audit storage... |
| V-204509 | Medium | The Red Hat Enterprise Linux operating system must off-load audit records onto a different system or media from the system being audited. | Information stored in one location is vulnerable to accidental or incidental deletion or alteration.
Off-loading is a common process in information systems with limited audit storage... |
| V-204464 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all files and directories have a valid group owner. | Files without a valid group owner may be unintentionally inherited if a group is assigned the same Group Identifier (GID) as the GID of the files without a valid group owner. |
| V-204545 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the chage command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-237633 | Medium | The Red Hat Enterprise Linux operating system must restrict privilege elevation to authorized personnel. | The sudo command allows a user to execute programs with elevated (administrator) privileges. It prompts the user for their password and confirms your request to execute a command by checking a... |
| V-255926 | Medium | The Red Hat Enterprise Linux operating system must have the screen package installed. | A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not log out because of the... |
| V-204592 | Medium | The Red Hat Enterprise Linux operating system must not permit direct logons to the root account using remote access via SSH. | Even though the communications channel may be encrypted, an additional layer of security is gained by extending the policy of not logging on directly as root. In addition, logging on with a... |
| V-219059 | Medium | The Red Hat Enterprise Linux operating system must disable the graphical user interface automounter unless required. | Automatically mounting file systems permits easy introduction of unknown devices, thereby facilitating malicious activity.
Satisfies: SRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163,... |
| V-204435 | Medium | The Red Hat Enterprise Linux operating system must not allow a non-certificate trusted host SSH logon to the system. | Failure to restrict system access to authenticated users negatively impacts operating system security. |
| V-204567 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/shadow. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204564 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/passwd. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-237634 | Medium | The Red Hat Enterprise Linux operating system must use the invoking user's password for privilege escalation when using "sudo". | The sudoers security policy requires that users authenticate themselves before they can use sudo. When sudoers requires authentication, it validates the invoking user's credentials. If the rootpw,... |
| V-204517 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the chown, fchown, fchownat, and lchown syscalls. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204516 | Medium | The Red Hat Enterprise Linux operating system must audit all executions of privileged functions. | Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised information system accounts, is a serious... |
| V-204515 | Medium | The Red Hat Enterprise Linux operating system must immediately notify the System Administrator (SA) and Information System Security Officer (ISSO) (at a minimum) when the threshold for the repository maximum audit record storage capacity is reached. | If security personnel are not notified immediately when the threshold for the repository maximum audit record storage capacity is reached, they are unable to expand the audit record storage... |
| V-204514 | Medium | The Red Hat Enterprise Linux operating system must immediately notify the System Administrator (SA) and Information System Security Officer (ISSO) (at a minimum) via email when the threshold for the repository maximum audit record storage capacity is reached. | If security personnel are not notified immediately when the threshold for the repository maximum audit record storage capacity is reached, they are unable to expand the audit record storage... |
| V-204513 | Medium | The Red Hat Enterprise Linux operating system must initiate an action to notify the System Administrator (SA) and Information System Security Officer ISSO, at a minimum, when allocated audit record storage volume reaches 75% of the repository maximum audit record storage capacity. | If security personnel are not notified immediately when storage volume reaches 75 percent utilization, they are unable to plan for audit record storage capacity expansion. |
| V-204512 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the audit system takes appropriate action when there is an error sending audit records to a remote system. | Taking appropriate action when there is an error sending audit records to a remote system will minimize the possibility of losing audit records.
One method of off-loading audit logs in Red Hat... |
| V-204459 | Medium | The Red Hat Enterprise Linux operating system security patches and updates must be installed and up to date. | Timely patching is critical for maintaining the operational availability, confidentiality, and integrity of information technology (IT) systems. However, failure to keep operating system and... |
| V-204457 | Medium | The Red Hat Enterprise Linux operating system must define default permissions for all authenticated users in such a way that the user can only read and modify their own files. | Setting the most restrictive default permissions ensures that when new accounts are created, they do not have unnecessary access. |
| V-204454 | Medium | The Red Hat Enterprise Linux operating system must enable the SELinux targeted policy. | Without verification of the security functions, security functions may not operate correctly and the failure may go unnoticed. Security function is defined as the hardware, software, and/or... |
| V-204453 | Medium | The Red Hat Enterprise Linux operating system must enable SELinux. | Without verification of the security functions, security functions may not operate correctly and the failure may go unnoticed. Security function is defined as the hardware, software, and/or... |
| V-204450 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the Datagram Congestion Control Protocol (DCCP) kernel module is disabled unless required. | Disabling DCCP protects the system against exploitation of any flaws in the protocol implementation. |
| V-204563 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the kmod command. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204560 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the init_module and finit_module syscalls. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-237635 | Medium | The Red Hat Enterprise Linux operating system must require re-authentication when using the "sudo" command. | Without re-authentication, users may access resources or perform tasks for which they do not have authorization.
When operating systems provide the capability to escalate a functional... |
| V-204588 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using RSA rhosts authentication. | Configuring this setting for the SSH daemon provides additional assurance that remote logon via SSH will require a password, even in the event of misconfiguration elsewhere. |
| V-204589 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. | Terminating an unresponsive SSH session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or... |
| V-204584 | Medium | The Red Hat Enterprise Linux operating system must implement virtual address space randomization. | Address space layout randomization (ASLR) makes it more difficult for an attacker to predict the location of attack code he or she has introduced into a process's address space during an attempt... |
| V-204585 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all networked systems have SSH installed. | Without protection of the transmitted information, confidentiality and integrity may be compromised because unprotected communications can be intercepted and either read or altered.
This... |
| V-204586 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all networked systems use SSH for confidentiality and integrity of transmitted and received information as well as information during preparation for transmission. | Without protection of the transmitted information, confidentiality and integrity may be compromised because unprotected communications can be intercepted and either read or altered.
This... |
| V-204587 | Medium | The Red Hat Enterprise Linux operating system must be configured so that all network connections associated with SSH traffic are terminated after 10 minutes of becoming unresponsive. | Terminating an unresponsive SSH session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or... |
| V-204580 | Medium | The Red Hat Enterprise Linux operating system must display the Standard Mandatory DoD Notice and Consent Banner immediately prior to, or as part of, remote access logon prompts. | Display of a standardized and approved use notification before granting access to the publicly accessible operating system ensures privacy and security notification verbiage used is consistent... |
| V-204581 | Medium | The Red Hat Enterprise Linux operating system must implement cryptography to protect the integrity of Lightweight Directory Access Protocol (LDAP) authentication communications. | Without cryptographic integrity protections, information can be altered by unauthorized users without detection.
Cryptographic mechanisms used for protecting the integrity of information include,... |
| V-204582 | Medium | The Red Hat Enterprise Linux operating system must implement cryptography to protect the integrity of Lightweight Directory Access Protocol (LDAP) communications. | Without cryptographic integrity protections, information can be altered by unauthorized users without detection.
Cryptographic mechanisms used for protecting the integrity of information include,... |
| V-204583 | Medium | The Red Hat Enterprise Linux operating system must implement cryptography to protect the integrity of Lightweight Directory Access Protocol (LDAP) communications. | Without cryptographic integrity protections, information can be altered by unauthorized users without detection.
Cryptographic mechanisms used for protecting the integrity of information include,... |
| V-233307 | Medium | The Red Hat Enterprise Linux operating system SSH daemon must prevent remote hosts from connecting to the proxy display. | When X11 forwarding is enabled, there may be additional exposure to the server and client displays if the sshd proxy display is configured to listen on the wildcard address. By default, sshd binds... |
| V-204441 | Medium | The Red Hat Enterprise Linux operating system must uniquely identify and must authenticate organizational users (or processes acting on behalf of organizational users) using multifactor authentication. | To assure accountability and prevent unauthenticated access, organizational users must be identified and authenticated to prevent potential misuse and compromise of the system.
Organizational... |
| V-204445 | Medium | The Red Hat Enterprise Linux operating system must be configured so that a file integrity tool verifies the baseline operating system configuration at least weekly. | Unauthorized changes to the baseline configuration could make the system vulnerable to various attacks or allow unauthorized access to the operating system. Changes to operating system... |
| V-204444 | Medium | The Red Hat Enterprise Linux operating system must prevent nonprivileged users from executing privileged functions to include disabling, circumventing, or altering implemented security safeguards/countermeasures. | Preventing nonprivileged users from executing privileged functions mitigates the risk that unauthorized individuals or processes may gain unnecessary access to information or... |
| V-204446 | Medium | The Red Hat Enterprise Linux operating system must be configured so that designated personnel are notified if baseline configurations are changed in an unauthorized manner. | Unauthorized changes to the baseline configuration could make the system vulnerable to various attacks or allow unauthorized access to the operating system. Changes to operating system... |
| V-204449 | Medium | The Red Hat Enterprise Linux operating system must be configured to disable USB mass storage. | USB mass storage permits easy introduction of unknown devices, thereby facilitating malicious activity.
Satisfies: SRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227 |
| V-204548 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the sudo command. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-250314 | Medium | The Red Hat Enterprise Linux operating system must elevate the SELinux context when an administrator calls the sudo command. | Preventing nonprivileged users from executing privileged functions mitigates the risk that unauthorized individuals or processes may gain unnecessary access to information or... |
| V-204618 | Medium | Network interfaces configured on the Red Hat Enterprise Linux operating system must not be in promiscuous mode. | Network interfaces in promiscuous mode allow for the capture of all network traffic visible to the system. If unauthorized individuals can access these applications, it may allow then to collect... |
| V-204511 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the audit system takes appropriate action when the audit storage volume is full. | Taking appropriate action in case of a filled audit storage volume will minimize the possibility of losing audit records.
One method of off-loading audit logs in Red Hat Enterprise Linux is with... |
| V-204599 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not permit Kerberos authentication unless needed. | Kerberos authentication for SSH is often implemented using Generic Security Service Application Program Interface (GSSAPI). If Kerberos is enabled through SSH, the SSH daemon provides a means of... |
| V-204598 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not permit Generic Security Service Application Program Interface (GSSAPI) authentication unless needed. | GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing... |
| V-204597 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH private host key files have mode 0640 or less permissive. | If an unauthorized user obtains the private SSH host key file, the host could be impersonated. |
| V-204596 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH public host key files have mode 0644 or less permissive. | If a public host key file is modified by an unauthorized user, the SSH service may be compromised. |
| V-204566 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/gshadow. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204617 | Medium | The Red Hat Enterprise Linux operating system must not send Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirects. | ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table, possibly... |
| V-204610 | Medium | The Red Hat Enterprise Linux operating system must use a reverse-path filter for IPv4 network traffic when possible on all interfaces. | Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems that are... |
| V-204611 | Medium | The Red Hat Enterprise Linux operating system must use a reverse-path filter for IPv4 network traffic when possible by default. | Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems which are... |
| V-204612 | Medium | The Red Hat Enterprise Linux operating system must not forward Internet Protocol version 4 (IPv4) source-routed packets by default. | Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security... |
| V-204613 | Medium | The Red Hat Enterprise Linux operating system must not respond to Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) echoes sent to a broadcast address. | Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks. |
| V-204565 | Medium | The Red Hat Enterprise Linux operating system must generate audit records for all account creations, modifications, disabling, and termination events that affect /etc/group. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204549 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the sudoers file and all files in the /etc/sudoers.d/ directory. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-204552 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the mount command and syscall. | Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.
At a minimum, the organization must audit the full-text recording of... |
| V-250313 | Medium | The Red Hat Enterprise Linux operating system must not allow privileged accounts to utilize SSH. | Preventing non-privileged users from executing privileged functions mitigates the risk that unauthorized individuals or processes may gain unnecessary access to information or... |
| V-214800 | Medium | The Red Hat Enterprise Linux operating system must implement the Endpoint Security for Linux Threat Prevention tool. | Adding endpoint security tools can provide the capability to automatically take actions in response to malicious behavior, which can provide additional agility in reacting to network threats.... |
| V-204437 | Medium | The Red Hat Enterprise Linux operating system must require authentication upon booting into single-user and maintenance modes. | If the system does not require valid root authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to... |
| V-204430 | Medium | The Red Hat Enterprise Linux operating system must be configured so that users must re-authenticate for privilege escalation. | Without re-authentication, users may access resources or perform tasks for which they do not have authorization.
When operating systems provide the capability to escalate a functional... |
| V-204431 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the delay between logon prompts following a failed console logon attempt is at least four seconds. | Configuring the operating system to implement organization-wide security implementation guides and security checklists verifies compliance with federal standards and establishes a common security... |
| V-204451 | Medium | The Red Hat Enterprise Linux operating system must disable the file system automounter unless required. | Automatically mounting file systems permits easy introduction of unknown devices, thereby facilitating malicious activity.
Satisfies: SRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163,... |
| V-251704 | Medium | The Red Hat Enterprise Linux operating system must not be configured to bypass password requirements for privilege escalation. | Without re-authentication, users may access resources or perform tasks for which they do not have authorization.
When operating systems provide the capability to escalate a functional... |
| V-204619 | Medium | The Red Hat Enterprise Linux operating system must be configured to prevent unrestricted mail relaying. | If unrestricted mail relaying is permitted, unauthorized senders could use this host as a mail relay for the purpose of sending spam or other unauthorized activity. |
| V-204609 | Medium | The Red Hat Enterprise Linux operating system must not forward Internet Protocol version 4 (IPv4) source-routed packets. | Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security... |
| V-244558 | Medium | Red Hat Enterprise Linux operating systems version 7.2 or newer booted with United Extensible Firmware Interface (UEFI) must have a unique name for the grub superusers account when booting into single-user mode and maintenance. | If the system does not require valid authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to all... |
| V-204603 | Medium | The Red Hat Enterprise Linux operating system must, for networked systems, synchronize clocks with a server that is synchronized to one of the redundant United States Naval Observatory (USNO) time servers, a time server designated for the appropriate DoD network (NIPRNet/SIPRNet), and/or the Global Positioning System (GPS). | Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time a particular event occurred on a system is critical when... |
| V-204602 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow compression or only allows compression after successful authentication. | If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection,... |
| V-204601 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon uses privilege separation. | SSH daemon privilege separation causes the SSH process to drop root privileges when not needed, which would decrease the impact of software vulnerabilities in the unprivileged section. |
| V-204600 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon performs strict mode checking of home directory configuration files. | If other users have access to modify user-specific SSH configuration files, they may be able to log on to the system as another user. |
| V-204614 | Medium | The Red Hat Enterprise Linux operating system must prevent Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages from being accepted. | ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An... |
| V-204615 | Medium | The Red Hat Enterprise Linux operating system must ignore Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages. | ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An... |
| V-204521 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the chmod, fchmod, and fchmodat syscalls. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204595 | Medium | The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon is configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms. | DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions. The only SSHv2 hash algorithm meeting this requirement is SHA.
The system will attempt to use the... |
| V-204524 | Medium | The Red Hat Enterprise Linux operating system must audit all uses of the setxattr, fsetxattr, lsetxattr, removexattr, fremovexattr, and lremovexattr syscalls. | Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an... |
| V-204461 | Low | The Red Hat Enterprise Linux operating system must be configured so that all Group Identifiers (GIDs) referenced in the /etc/passwd file are defined in the /etc/group file. | If a user is assigned the GID of a group not existing on the system, and a group with the GID is subsequently created, the user may have unintended rights to any files associated with the group. |
| V-255927 | Low | The Red Hat Enterprise Linux operating system must restrict access to the kernel message buffer. | Restricting access to the kernel message buffer limits access only to root. This prevents attackers from gaining additional system information as a non-privileged user. |
| V-204493 | Low | The Red Hat Enterprise Linux operating system must be configured so that a separate file system is used for user home directories (such as /home or an equivalent). | The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing. |
| V-204496 | Low | The Red Hat Enterprise Linux operating system must use a separate file system for /tmp (or equivalent). | The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing. |
| V-204494 | Low | The Red Hat Enterprise Linux operating system must use a separate file system for /var. | The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing. |
| V-204495 | Low | The Red Hat Enterprise Linux operating system must use a separate file system for the system audit data path. | The use of separate file systems for different paths can protect the system from failures resulting from a file system becoming full or failing. |
| V-204498 | Low | The Red Hat Enterprise Linux operating system must be configured so that the file integrity tool is configured to verify Access Control Lists (ACLs). | ACLs can provide permissions beyond those permitted through the file mode and must be verified by file integrity tools. |
| V-204499 | Low | The Red Hat Enterprise Linux operating system must be configured so that the file integrity tool is configured to verify extended attributes. | Extended attributes in file systems are used to contain arbitrary data and file metadata with security implications. |
| V-204576 | Low | The Red Hat Enterprise Linux operating system must limit the number of concurrent sessions to 10 for all accounts and/or account types. | Operating system management includes the ability to control the number of users and user sessions that utilize an operating system. Limiting the number of allowed users and sessions per user is... |
| V-204486 | Low | The Red Hat Enterprise Linux operating system must mount /dev/shm with secure options. | The "noexec" mount option causes the system to not execute binary files. This option must be used for mounting any file system not containing approved binary files as they may be incompatible.... |
| V-204452 | Low | The Red Hat Enterprise Linux operating system must remove all software components after updated versions have been installed. | Previous versions of software components that are not removed from the information system after updates have been installed may be exploited by adversaries. Some information technology products... |
| V-204608 | Low | For Red Hat Enterprise Linux operating systems using DNS resolution, at least two name servers must be configured. | To provide availability for name resolution services, multiple redundant name servers are mandated. A failure in name resolution could lead to the failure of security functions requiring name... |
| V-204605 | Low | The Red Hat Enterprise Linux operating system must display the date and time of the last successful account logon upon logon. | Providing users with feedback on when account accesses last occurred facilitates user recognition and reporting of unauthorized account use. |
